A mechanical seal comprises a “floating” component which is mounted axially movable around the rotary shaft of, for example, a pump or a “static” component which is axially fixed, typically being secured to a housing. The floating component has a flat annular end face, i.e. its seal face, directed towards a complementary seal face of the static component. The floating component is urged towards the static component to close the seal faces together to form a sliding face seal, usually by means of one or more spring members. In use, one of the floating and static components rotates; this component is therefore referred to as the rotary component. The other of the floating and static components does not rotate and is referred to as the stationary component.
Those seals whose floating component is rotary are described as rotary seals. If the floating component is stationary, the seal is referred to as a stationary seal.
If the sliding seal between the rotary and stationary components are assembled and pre-set prior to despatch from the mechanical seal manufacturing premises, the industry terminology for this is “cartridge seal”. If the rotary and stationary components are despatched individually (unassembled) from the mechanical seal manufacturing premises, the industry terminology for this is “component seal”.
The present invention relates to component seals, which can be used in numerous applications and with various products. The sale of the products is price sensitive due to the relatively simple and common technology used. For this reason, modularity use of the same components in different seals in the design is a key way of reducing the associated costs of manufacturing and stocking of parts. For this reason it is important that particular components can be replaced with ones of a differing material to allow it to be used in a different application.
In the case of o-rings, which are used in the mechanical seals to provide a seal between the mechanical seal and the pump components, modularity can be hindered if the rigidity of the material that is required for the o-ring does not allow it to be fitted into the component which it resides.